Common Writing Mistakes & Corrections

The Rule: The verb in a sentence must agree in number with its subject. If the subject is singular, use a singular verb. If it's plural, use a plural verb.

Common traps: compound subjects joined by neither/nor use a singular verb when both elements are singular. Names followed by descriptive phrases still take singular verbs. Phrases like he doesn't (not he don't) follow this same rule.

Watch out for sentences where the subject and verb are separated by a long phrase — writers often mistakenly agree the verb with the nearest noun instead of the true subject.

The Core Confusion: English has several look-alike pairs where an apostrophe signals a contraction, not possession:

• it's = it is  |  its = belonging to it
• you're = you are  |  your = belonging to you
• they're = they are  |  their = belonging to them  |  there = place
• who's = who is  |  whose = belonging to whom

Quick test: Substitute the full phrase. If "it is" fits, use it's. If not, use its.

A / An — Use before singular count nouns that are not specific. Use an before vowel sounds.
The — Use when the noun is specific or both speaker and listener know which one. Use the for unique things and for specific/local references.
No article — Proper nouns (names of people, most cities, parks) and general plural or non-count nouns typically take no article.

Examples: I need a pen (any pen).  |  Pass me the pen on the desk (specific).  |  Yosemite National Park is beautiful (proper noun → no article).

The Problem: Prepositions in English are often idiomatic — there's no consistent logical rule. You must learn which preposition collocates with which adjective or verb.

Common adjective + preposition pairs:
• interested in  |  great at  |  good at / for  |  afraid of  |  dependent on  |  responsible for

Common verb + preposition pairs:
• depend on  |  consist of  |  result in  |  refer to  |  comply with

The Rule: Once you establish a tense, maintain it unless there's a clear logical or temporal reason to shift. Time-marker words are your guide:

• Past markers: yesterday, last week, ago, in [past year] → use simple past or past continuous
• Present/Habit: routines and general truths → use simple present
• Future markers: tomorrow, next week, will, shall → use future tense

Mixing tenses mid-narrative (e.g., writing about a past event using present tense, then past tense) confuses readers about when events occurred.

Three most common comma rules:

1. Introductory phrases/clauses: When a sentence begins with an adverbial phrase or clause, follow it with a comma.
After going to the dentist, I learned to floss daily.

2. Direct quotations: Place a comma before (or after) a reporting verb and its direct quote.
The dentist said, "You need to floss more."

3. Compound sentences: When joining two independent clauses with a coordinating conjunction (for, and, nor, but, or, yet, so — FANBOYS), use a comma before the conjunction.
He requested a raise, and I should consider it.

Collocations are word combinations that sound natural to native speakers. Using the wrong word in a common collocation marks writing as non-fluent.

Affect vs. Effect
• affect = verb (to influence): The weather affects my mood.
• effect = noun (the result): The effect of the weather on my mood…

Common verb collocations:
• give/do a presentation (both acceptable, but give is more idiomatic)
• buy/purchase some time → buy some time (fixed phrase meaning to delay)
• make/do a mistake → make a mistake (not "do a mistake")

Formal vs. Informal Register: Different contexts demand different levels of formality. Academic papers, business letters, and professional emails require formal register — no casual idioms, slang, contractions (in most cases), or conversational reductions.

Common informal → formal substitutions:
• gonna → going to
• wanna → want to
• kinda / sort of → somewhat / rather
• Idioms like in the nick of time or piece of cake → avoid in formal contexts
• straightforward (one word) over casual phrasing

Always ask: Would this phrasing appear in a published journal article or a legal document? If not, revise it.